1. Field of the Invention
The present invention relates to a plasma display panel performing an AC discharge type matrix display and a driving method thereof.
2. Description of the Related Art
A first prior art of a conventional plasma display panel and a driving method thereof will be described, referring to the drawings. FIG. 1 is a partially cross sectional view illustrating the conventional plasma display panel. In the plasma display panel, two isolation substrates 1a and 1b of a front surface and a rear surface made of glass are provided.
On the isolation substrate 1a, transparent scanning electrodes 2 and sustaining electrodes 3 are formed, and trace electrodes 4 are arranged to overlap the scanning electrodes 2 and the sustaining electrodes 3 in order to make the resistance values of the electrodes be lowered. Also, a first dielectric layer 9 is formed to cover the scanning electrode 2 and the sustaining electrode 3, and a protective layer 10 made of magnesium oxide or the like is formed to protect the dielectric layer 9 from discharge.
On the isolation substrate 1b, data electrodes 5 that are extended in perpendicular to the scanning electrodes 2 and the sustaining electrodes 3 are formed. Also, a second dielectric layer 11 is formed to cover the data electrode 5. On the dielectric layer 11, a partition wall 7 extended in the same direction as that of the data electrode 5 is formed to partition a display cell that is a unit of display. Moreover, on the side surface of the partition wall 7 and the surface of the dielectric layer 11 on which the partition wall 7 is not formed, a fluorescent layer 8 is formed to transform ultraviolet light generated by discharging of discharge gas into visible light.
A space sandwiched between the isolation substrates 1a and 1b and partitioned by the partition wall 7 becomes a discharge space 6 filled by discharge gas consisting of helium, neon, xenon, and the like, or mixture of gases thereof.
In the above-configured plasma display panel, surface discharge 100 is generated between the scanning electrode 2 and the sustaining electrode 3.
FIG. 2 is a schematic diagram illustrating an electrode arrangement of the conventional plasma display panel. One display cell 12 is provided on the intersection of one scanning electrode 2, one sustaining electrode 3, and one data electrode 5, which is in perpendicular to the electrodes. The scanning electrode 2 is connected to a scan driver integrated circuit IC (not shown) so as to individually apply a scan voltage pulse. Since the sustaining electrode 3 applies only a common waveform, it is all electrically commonly connected on the end portion of the panel or driving circuit.
Subsequently, the selective display operation of the display cell will be described. FIG. 3 is a timing chart illustrating a voltage pulse applied to each electrode. In FIG. 3, a period A is a pre-discharge period for easily generating discharge, a period B is a selecting operation period for selecting ON/OFF of display of each display cell, a period C is a sustaining discharge period for performing display discharge in all the selected display cells, and a period D is a sustaining erasing period for stopping display discharge.
First, in the pre-discharge period A, with applying a voltage exceeding a discharge start threshold voltage between the scanning electrode 2 and the sustaining electrode 3, discharge is generated in all the display cells 12 so that wall charge is formed. After that, with using weak discharge due to a dull pulse, wall charge formed on the scanning electrode 2 and the sustaining electrode 3 is neutralized and erased.
Subsequently, in the selecting operation period B, with sequentially applying a scan pulse to each scanning electrode 2 and simultaneously applying a data pulse to the data electrode 5 in accordance with an image data, wall charge is formed only on the scanning electrode 2 of the display cell 12 to perform display.
After that, in the sustaining discharge period C, sustaining pulses having inverted phases with each other are applied to all the scanning electrodes 2 and all the sustaining electrodes 3. As a result, discharge for display is generated only in the display cell 12 in which the wall charge is formed during the selecting operation period B.
In the sustaining erasing period D, the wall charge is neutralized and erased by a dull pulse, thereby returning to the initial state.
In the practical plasma display driving, a period from the above-mentioned pre-discharge period A or the selecting operation period B to the sustaining erasing period D has been one sub-field, a combination of a plurality of sub-fields in which the number of pulses is changed in the sustaining discharge period C has been one field, and display brightness has been regulated with selection of ON/OFF of each sub-field. At this time, sub-field selection state for input gradation is determined referring to a lookup table (LUT). In the LUT, the sub-field selection state for all the input gradation is uniquely described.
In addition, as described above, in a manner that the sustaining period when only sustaining discharge is performed is independent of other periods, brightness can be controlled by means of changing a cycle of sustaining pulse applied in the sustaining discharge period C, and high brightness can be achieved by means of supplying high frequency.
Subsequently, a second prior art of a conventional display penal and a driving method thereof will be described. FIG. 4 is a schematic diagram illustrating an electrode arrangement in a conventional plasma display panel having an electrode structure in which a scanning electrode is shared between upper and lower adjacent display cells. Each discharge space of two display cells 12 sharing the scanning electrode 2 is physically separated by a partition wall (not shown in FIG. 4) formed on the scanning electrode 2. The plasma display panel having such a structure is disclosed, for example, in Japanese Patent No. 2629944.
FIG. 5 is a timing chart illustrating the conventional driving method disclosed in Japanese Patent No. 2629944. In the interval of the sustaining pulse, a pre-discharge pulse and a selective erasing pulse are sequentially applied to a scanning electrode Y, and the pre-discharge pulse is selectively applied to a sustaining electrode X in the upper and lower lines so that the upper and lower display lines are individually selected.
Also, a plasma display panel (a third prior art) having a structure in which display cells are divided into a plurality of blocks and a plurality of scanning electrodes are shared in the blocks is disclosed in Japanese Patent Laid-Open No. 2000-56731. In the conventional plasma display panel, an erasing selection is adapted in the same manner as that of the above-mentioned Japanese Patent No. 2629944.
In the conventional plasma display panel shown in the first prior art, because each scanning electrode 2 is individually selected, the output terminals of scan driver IC are needed as the same number as the scanning electrodes 2 (that is, the number of display lines). On the other hand, because high withstand voltage and high speed of response are needed for the scan driver IC, its price is high so that its using quantity needs to be reduced in order to cut down cost.
Also, in the conventional plasma display panel shown in the second prior art, the number of scanning electrodes 2 is reduced by half with respect to the number of display lines so that the number of scan drivers IC can be reduced by half. However, there are problems in the driving method disclosed in Japanese Patent No. 2629944, as follows.
Firstly, two kinds of pulses of a pulse Vwy for illuminating all the display cells on the display lines and a pulse Vey for selecting the display cells need to be sequentially applied to the scanning electrode. And, in the practical driving, a pulse for stopping discharge of each display line (not shown) needs to be sequentially applied to the scanning electrode. Consequently, a scan circuit including the scan driver IC becomes complex, thereby causing a problem that cost merit that the number of scan drivers IC is reduced cannot be sufficiently achieved.
Secondly, because many pulses are applied within a constant pulse for display (a sustaining pulse), it is difficult to shorten a cycle of the sustaining pulse. Because brightness in the plasma display panel is determined by the number of discharge times, and as a result, there is a problem that high brightness cannot be easily achieved.
Thirdly, because several times (about 5 times) of discharges are performed in the (non-selected) display cell in which display is not performed, there is a problem that brightness of black level is increased so that contrast of display image is deteriorated.
In the erasing selective type plasma display panel as the second and third prior arts, there is a problem that brightness of black level is high and contrast of whole image plane is lacking so that sufficient quality of image cannot be achieved.
It is an object of the present invention to provide a plasma display panel in which high contrast can be obtained, and cost is reduced without reducing brightness, and progressive driving is available, and a driving method thereof.
According to one aspect of the present invention, a plasma display panel comprises: a first substrate and a second substrate disposed opposite to each other; a plurality of scanning electrodes provided on a face side of the first substrate opposite to the second substrate and extended parallel to a first direction; a plurality of sustaining electrodes provided by two between adjacent two scanning electrodes among the scanning electrodes; a plurality of data electrodes provided on a face side of the second substrate opposite to the first substrate and extended to a second direction perpendicular to the first direction; a dielectric layer covering the scanning electrodes and the sustaining electrodes; and a partition wall partitioning the scanning electrodes into two regions in the second direction. The scanning electrodes are shared between adjacent display lines. The sustaining electrodes are separated into a first sustaining electrode group in which a plurality of the sustaining electrodes disposed at one side of the scanning electrode are commonly connected and a second sustaining electrode group in which a plurality of sustaining electrodes disposed at the other side of the scanning electrode are commonly connected to be independently driven.
In the present invention, the scanning electrodes are shared between adjacent display lines and the plurality of sustaining electrodes are separated into a first sustaining electrode group in which a plurality of the sustaining electrodes disposed at one side of the scanning electrode are commonly connected and a second sustaining electrode group in which a plurality of sustaining electrodes disposed at the other side of the scanning electrode are commonly connected to be independently driven. Accordingly, display line can be selected by the driving method of a combination of the scanning electrodes and the sustaining electrodes disposed at the both side thereof. Consequently, the numbers of outputs of scan drivers IC can be reduced about by half of the number of display lines.
According to another aspect of the present invention, a driving method of a plasma display panel, the plasma display panel having: a first substrate and a second substrate disposed opposite to each other; a plurality of scanning electrodes provided on a face side of the first substrate opposite to the second substrate and extended parallel to a first direction, the scanning electrodes being commonly connected by a plural number in a sequence of order to make scanning electrode groups; a plurality of sustaining electrodes disposed by one between adjacent two scanning electrodes among the scanning electrodes, the sustaining electrodes being commonly connected so that the sustaining electrodes forming display lines between the scanning electrodes belonging to one of the scanning electrode groups belong to different sustaining electrode groups; a plurality of data electrodes provided on a face side of the second substrate opposite to the first substrate and extended to a second direction perpendicular to the first direction; and a dielectric layer covering the scanning electrodes and the sustaining electrodes, the method comprises the steps of: generating a pre-discharge between one of the sustaining electrode groups and each of the scanning electrode groups; and performing a selecting operation in accordance with an image data of each of display cells in display lines generated with the pre-discharge. Generating the pre-discharge and performing the selecting operation are repeated while sequentially selecting the sustaining electrode group. At least one of the steps of performing the selecting operation has a step of generating an opposite discharge between the scanning electrode and the data electrode in a display cell performing display, thereby forming wall charge on the scanning electrode and the sustaining electrode.
According to another aspect of the present invention, a driving method of a plasma display panel, the plasma display panel having: a first substrate and a second substrate disposed opposite to each other; a plurality of scanning electrodes provided on a face side of the first substrate opposite to the second substrate and extended parallel to a first direction, the scanning electrodes being shared between adjacent display lines; a plurality of sustaining electrodes disposed by two between adjacent two scanning electrodes among the scanning electrodes, the sustaining electrodes being separated into a first sustaining electrode group in which a plurality of sustaining electrodes disposed at one side of the scanning electrode are commonly connected and a second sustaining electrode group in which a plurality of sustaining electrodes disposed at the other side of the scanning electrode are commonly connected; a plurality of data electrodes provided on a face side of the second substrate opposite to the first substrate and extended to a second direction perpendicular to the first direction; a dielectric layer covering the scanning electrodes and the sustaining electrodes; and a partition wall partitioning the scanning electrodes into two regions in the second direction, the method comprises the steps of: generating a first pre-discharge between the first sustaining electrode group and the scanning electrodes; performing a selecting operation in display lines generated with the first pre-discharge; generating a second pre-discharge between the second sustaining electrode group and the scanning electrodes; and performing a selecting operation in display lines generated with the second pre-discharge.
According to another aspect of the present invention, a driving method of a plasma display panel, the plasma display panel having: a first substrate and a second substrate disposed opposite to each other; a plurality of scanning electrodes provided on a face side of the first substrate opposite to the second substrate and extended parallel to a first direction, the scanning electrodes being shared between adjacent display lines; a plurality of sustaining electrodes disposed by one between adjacent two scanning electrodes among the scanning electrodes, the sustaining electrodes being shared between adjacent display lines and being separated into a first sustaining electrode group in which an odd number of the sustaining electrodes are commonly connected and a second sustaining electrode group in which an even number of the sustaining electrodes are commonly connected; a plurality of data electrodes provided on a face side of the second substrate opposite to the first substrate and extended to a second direction perpendicular to the first direction; a dielectric layer covering the scanning electrodes and the sustaining electrodes; and a partition wall partitioning the scanning electrodes and the sustaining electrodes into two regions, respectively, in the second direction, the method comprises the steps of: generating a first pre-discharge between the first sustaining electrode group and the scanning electrodes; performing a selecting operation in display lines generated with the first pre-discharge; generating a second pre-discharge between the second sustaining electrode group and the scanning electrodes; and performing a selecting operation in display lines generated with the second pre-discharge.
In the present invention, pre-discharge and selecting operation are performed in the display line included in a first sustaining electrode group, pre-discharge and selecting operation are sequentially performed every display line included in sustaining electrode groups, and then, selecting operation is performed in all the display lines, thereafter, being transferred to a sustaining discharge period for performing sustaining discharge for display. Accordingly, because the selecting operation is performed only in the display line where the pre-discharge was generated, the selecting operation can be individually performed even in the adjacent display lines that share the scanning electrode.
An erasing selective type driving method can be available by providing, in at least one of the steps of generating the pre-discharge and performing the associated selecting operations, with the steps of forming wall charges having an opposite polarity with each other on the scanning electrode and the sustaining electrode, and generating opposite discharge between the scanning electrode and the sustaining electrode to erase wall discharge in the display cell where display is not performed. Consequently, with forming wall charge due to pre-discharge only in the sustaining electrode group where the selecting operation is performed, the selecting operation can be prevented from being performed in the display lines included in the other sustaining electrode group.
At that time, after the step of erasing the wall charge, by inverting polarity of wall charge by generating discharge in the display cell in which wall charge was not erased, erroneous erasing of necessary wall charge in the address period of the next sustaining electrode group can be avoided.
Also, an input selective type driving method can be available by providing, in at least one of the steps of performing the selecting operations, with the step of generating opposite discharge between the scanning electrode and the data electrode in a display cell in which display is performed, thereby forming wall charges on the scanning electrode and the sustaining electrode. In such an input selective type selecting operation, with neutralizing and erasing wall charge by pre-discharge only in the sustaining electrode group which performs the selecting operation, performing a selecting operation in the display line included in other sustaining electrode group can be avoided.
Also, by providing, in the step of generating a first pre-discharge, with the steps of forming wall charge having an opposite polarity to that of a voltage pulse applied to the scanning electrode by pre-discharge on all of the scanning electrodes, and applying an erasing pulse between the first sustaining electrode group and the scanning electrode to erase wall charge by pre-discharge; in the step of performing a selecting operation in the display line generated with the first pre-discharge, with the steps of sustaining a voltage of the first sustaining electrode group as a voltage for generating sustaining discharge between the scanning electrode, and generating opposite discharge between the scanning electrode and the data electrode in a display cell which performs display in the display line in which erasing of wall charge is performed by the pre-discharge, thereby forming wall charge; in the step of generating the second pre-discharge, with the step of applying an erasing pulse between the second sustaining electrode group and the scanning electrode to erase wall charge by the pre-discharge; in the step of performing a selecting operation in a display line generated with the second pre-discharge, with the steps of sustaining a voltage of the first sustaining electrode group as a voltage for not generating sustaining discharge between the scanning electrode, and generating opposite discharge between the scanning electrode and the data electrode in a display cell which performs display in the display line in which erasing of wall charge is performed by the pre-discharge, thereby forming wall charge, in such an input selective type selecting operation, in case that a side included in the first sustaining electrode group is not selected in the display cell which shares the scanning electrode, and a side included in the second sustaining electrode group is selected, although opposite discharge is generated even in the display cell included in the first sustaining electrode group in the address period of the display cell comprising sustaining electrode belonging to the second sustaining electrode group, because the first sustaining electrode group is sustained with such a voltage that sufficient discharge is not generated between the scanning electrode, wall charge is not generated on the scanning electrode and the sustaining electrode, and generation of discharge in the sustaining discharge period can be avoided.
According to another aspect of the present invention, a driving method of a plasma display panel, the plasma display panel having: a first substrate and a second substrate disposed opposite to each other; a plurality of scanning electrodes provided on a face side of the first substrate opposite to the second substrate and extended parallel to a first direction, the scanning electrodes being shared between adjacent display lines; a plurality of sustaining electrodes disposed by two between adjacent two scanning electrodes among the scanning electrodes, the sustaining electrodes being separated into a first sustaining electrode group in which a plurality of sustaining electrodes disposed at one side of the scanning electrode are commonly connected and a second sustaining electrode group in which a plurality of sustaining electrodes disposed at the other side of the scanning electrode are commonly connected; a plurality of data electrodes provided on a face side of the second substrate opposite to the first substrate and extended to a second direction perpendicular to the first direction; a dielectric layer covering the scanning electrodes and the sustaining electrodes; and a partition wall partitioning the scanning electrodes into two regions in the second direction, the method comprises the steps of: forming wall charge in a display cell having the sustaining electrode belonging to the first sustaining electrode group on the basis of image data, thereby the same polarity of wall charge is formed in a display cell sharing the scanning electrode and data electrode with the display cell and having the sustaining electrode belonging to the second sustaining electrode group; erasing wall charge formed in a display cell having the sustaining electrode belonging to the second sustaining electrode group; and forming wall charge in a display cell having the sustaining electrode belonging to the second sustaining electrode group on the basis of display data.
According to another aspect of the present invention, a driving method of a plasma display panel, the plasma display panel having: a first substrate and a second substrate disposed opposite to each other; a plurality of scanning electrodes provided on a face side of the first substrate opposite to the second substrate and extended parallel to a first direction, the scanning electrodes being shared between adjacent display lines; a plurality of sustaining electrodes disposed by one between adjacent two scanning electrodes among the scanning electrodes, the sustaining electrodes being shared between adjacent display lines and being separated into a first sustaining electrode group in which an odd number of the sustaining electrodes are commonly connected and a second sustaining electrode group in which an even number of the sustaining electrodes are commonly connected; a plurality of data electrodes provided on a face side of the second substrate opposite to the first substrate and extended to a second direction perpendicular to the first direction; a dielectric layer covering the scanning electrodes and the sustaining electrodes; and a partition wall partitioning the scanning electrodes and the sustaining electrodes into two regions, respectively, in the second direction, the method comprises the steps of: forming wall charge in a display cell having the sustaining electrode belonging to the first sustaining electrode group on the basis of image data, thereby the same polarity of wall charge is formed in a display cell sharing the scanning electrode and data electrode with the display cell and having the sustaining electrode belonging to the second sustaining electrode group; erasing wall charge formed in a display cell having the sustaining electrode belonging to the second sustaining electrode group; and forming wall charge in a display cell having the sustaining electrode belonging to the second sustaining electrode group on the basis of display data.
According to another aspect of the present invention, a driving method of a plasma display panel, the plasma display panel having: a first substrate and a second substrate disposed opposite to each other; a plurality of scanning electrodes provided on a face side of the first substrate opposite to the second substrate and extended parallel to a first direction, the scanning electrodes being shared between adjacent display lines; a plurality of sustaining electrodes disposed by two between adjacent two scanning electrodes among the scanning electrodes, the sustaining electrodes being separated into a first sustaining electrode group in which a plurality of sustaining electrodes disposed at one side of the scanning electrode are commonly connected and a second sustaining electrode group in which a plurality of sustaining electrodes disposed at the other side of the scanning electrode are commonly connected; a plurality of data electrodes provided on a face side of the second substrate opposite to the first substrate and extended to a second direction perpendicular to the first direction; a dielectric layer covering the scanning electrodes and the sustaining electrodes; and a partition wall partitioning the scanning electrodes into two regions in the second direction, the method comprises the steps of: forming wall charges having different polarities between a display cell having the sustaining electrode belonging to the first sustaining electrode group and a display cell having the sustaining electrode belonging to the second sustaining electrode group, on the scanning electrode and the sustaining electrode; erasing the wall charge in a display cell having the sustaining electrode belonging to the first sustaining electrode group on the basis of display data; inverting the polarity of said wall charges, respectively, in a display cell having said sustaining electrode belonging to said first and second sustaining electrode group; and erasing the wall charge in a display cell having the sustaining electrode belonging to the second sustaining electrode group on the basis of display data.
According to another aspect of the present invention, a driving method of a plasma display panel, the plasma display panel having: a first substrate and a second substrate disposed opposite to each other; a plurality of scanning electrodes provided on a face side of the first substrate opposite to the second substrate and extended parallel to a first direction, the scanning electrodes being shared between adjacent display lines; a plurality of sustaining electrodes disposed by one between adjacent two scanning electrodes among the scanning electrodes, the sustaining electrodes being shared between adjacent display lines and being separated into a first sustaining electrode group in which an odd number of the sustaining electrodes are commonly connected and a second sustaining electrode group in which an even number of the sustaining electrodes are commonly connected; a plurality of data electrodes provided on a face side of the second substrate opposite to the first substrate and extended to a second direction perpendicular to the first direction; a dielectric layer covering the scanning electrodes and the sustaining electrodes; and a partition wall partitioning the scanning electrodes and the sustaining electrodes into two regions, respectively, in the second direction, the method comprises the steps of: forming wall charges having different polarities between a display cell having the sustaining electrode belonging to the first sustaining electrode group and a display cell having the sustaining electrode belonging to the second sustaining electrode group, on the scanning electrode and the sustaining electrode; erasing the wall charge in a display cell having the sustaining electrode belonging to the first sustaining electrode group on the basis of display data; inverting the polarity of said wall charges, respectively, in a display cell having said sustaining electrode belonging to said first and second sustaining electrode group; and erasing the wall charge in a display cell having the sustaining electrode belonging to the second sustaining electrode group on the basis of display data.
By employing such a driving method, the number of driving circuits for driving the sustaining electrode groups, which are driven with each other divided is reduced. As a result, reduction of cost can be achieved.
Also, in the step of addressing, a step of changing a sequence of selecting operations every field consisting of one image plane between a plurality of the display lines or between a display line including the sustaining electrode belonging to the first sustaining electrode group and a display line including the sustaining electrode belonging to the second sustaining electrode group can be provided. In the input selective type, opposite discharge at the time of input is generated even in the non-selective type only in the display cell included in the first sustaining electrode group. Although the intensity of opposite discharge itself is not so intense, when it is generated only in the first sustaining electrode group, there is a case that in all the panels, linear noise occurs with a pitch of twice of display line pitch. However, as above described, it can be prevented from being acknowledged as noise with changing the addressing sequence by field to average discharge due to unnecessary input in all the panels.
A step of changing a sequence of the selecting operation in every step of address or in plural times of steps of address between a plurality of display lines or between the display line including the sustaining electrode belonging to the first sustaining electrode group and the display line including the sustaining electrode belonging to the second sustaining electrode group can be provided. As described above, in some cases of fixing the addressing sequence, although there is a case that linear noise may occur, because the selection of each sub-field is considered as substantially random in a natural image, it can be prevented from being acknowledged as noise with changing the addressing sequence by sub-field to average discharge due to unnecessary input in all the panels.
If changing the address sequence by sub-field and changing the address sequence by field are combined, the discharge due to unnecessary input can be further averaged.
According to another aspect of the present invention, a driving method of a plasma display panel, the plasma display panel having: a first substrate and a second substrate disposed opposite to each other; a plurality of scanning electrodes provided on a face side of the first substrate opposite to the second substrate and extended parallel to a first direction, the scanning electrodes being shared between adjacent display lines; a plurality of sustaining electrodes disposed by two between adjacent two scanning electrodes among the scanning electrodes, the sustaining electrodes being separated into a first sustaining electrode group in which a plurality of sustaining electrodes disposed at one side of the scanning electrode are commonly connected and a second sustaining electrode group in which a plurality of sustaining electrodes disposed at the other side of the scanning electrode are commonly connected; a plurality of data electrodes provided on a face side of the second substrate opposite to the first substrate and extended to a second direction perpendicular to the first direction; a dielectric layer covering the scanning electrodes and the sustaining electrodes; and a partition wall partitioning the scanning electrodes into two regions in the second direction, the method comprises the step of: selecting subfield in consideration of each input gradation level of two display cells sharing the scanning electrode and data electrode, a plurality of gradation levels being expressed with a combination of the selected subfields.
According to another aspect of the present invention, a driving method of a plasma display panel, the plasma display panel having: a first substrate and a second substrate disposed opposite to each other; a plurality of scanning electrodes provided on a face side of the first substrate opposite to the second substrate and extended parallel to a first direction, the scanning electrodes being shared between adjacent display lines; a plurality of sustaining electrodes disposed by one between adjacent two scanning electrodes among the scanning electrodes, the sustaining electrodes being shared between adjacent display lines and being separated into a first sustaining electrode group in which an odd number of the sustaining electrodes are commonly connected and a second sustaining electrode group in which an even number of the sustaining electrodes are commonly connected; a plurality of data electrodes provided on a face side of the second substrate opposite to the first substrate and extended to a second direction perpendicular to the first direction; a dielectric layer covering the scanning electrodes and the sustaining electrodes; and a partition wall partitioning the scanning electrodes and the sustaining electrodes into two regions, respectively, in the second direction, the method comprises the step of: selecting subfield in consideration of each input gradation level of two display cells sharing the scanning electrode and data electrode, a plurality of gradation levels being expressed with a combination of the selected subfields.
Selecting subfield may comprise a step of considering a relation between an input gradation level of the both display cells and an amount of light emission due to interference of the both display cells. It is preferable that the selecting subfield may be performed such that difference between output gradation level including an amount of light emission due to the interference of the both display cells and the input gradation level is minimized.
According to these driving methods, unnecessary light emission (crosstalk) generated between the adjacent display cells is used as a part of display light in accordance with the sub-field selection state in each display cell. Thus, deviation between input gradation and display gradation (output gradation) due to the unnecessary light emission is remarkably suppressed.
In accordance with a plasma display panel and a driving method thereof according to the present invention, because it can be controlled whether the selection is performed by a pre-discharge performed between sustaining electrode corresponding to each scanning electrode or not, the number of outputs of scan driver IC required for display can be reduced. Also, because a sustaining discharge period is shared in all the display lines and only the sustaining discharge can be performed, frequency of sustaining discharge pulse can be increased and then high brightness can be easily achieved.
Using the step of input selective type, brightness of black level can be sufficiently lowered so that high contrast can be achieved.
At least scanning electrode, preferably, including sustaining electrode, can be shared between the upper and lower adjacent display cells so that the number of metal trace electrodes can be reduced and opening rate can be increased.
In such a manner, cost of circuit can be reduced with reducing the substantial number of scanning electrodes with respect to the number of display lines, namely, the number of outputs of scan drivers IC. Also, driving for controlling ON/OFF of display in all the display cells, that is, a complete progressive driving can be achieved in all the fields and sub-fields. Also, even in case where crosstalk occurs, disorder of gradation can be suppressed low. And, high sustaining frequency can be used, and because non-display brightness can be suppressed to be low, image display of high brightness and high contrast can be achieved.